Lexus 2013 IS250 Owner's Manual page 296

294
4-5. Using the driving support systems
The Rear Crossing Traffic Alert function detection areas
The areas that vehicles can be detected in are outlined below.
To give the driver a more consistent time to react, the buzzer can alert for
faster vehicles from farther away.
Example:
Approaching vehicle

The Rear Crossing Traffic Alert function is operational when

The BSM main switch is set to on.

The shift lever is in R.

Vehicle speed is less than approximately 8 km/h (5 mph).

Approaching vehicle speed is between approximately 8 km/h (5 mph) and 28
km/h (18 mph).
IS250_EE(OM53B11E)
Fast 28 km/h (18 mph)
Slow 8 km/h (5 mph)
1
Speed
20 m (65 ft.)
5.5 m (18 ft.)
Approximate
alert distance